*The following content is generated by AI and is for reference only.
<h3>Overview</h3>
<p><strong>Cetirizine</strong> is a second-generation antihistamine synthesized via condensation of hydroxyzine derivatives. Its molecular formula is <strong>C21H25ClN2O3</strong> (CAS No. 83837-69-0).</p>
<h3>Application</h3>
<ul>
<li>Allergy pharmaceuticals: Treatment of seasonal and perennial rhinitis.</li>
<li>Dermatology: Management of chronic idiopathic urticaria.</li>
<li>Ophthalmology: Relief of ocular itching associated with allergic conjunctivitis.</li>
</ul>
<h3>Precautions</h3>
<p>Contraindicated in severe renal impairment; requires dose adjustment. Store below 25°C in dry, light-resistant containers. Handle with PPE to avoid inhalation or skin contact during manufacturing.</p>